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Disorder screening near the Mott-Anderson transition

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 نشر من قبل Maria Carolina O. Aguiar
 تاريخ النشر 2007
  مجال البحث فيزياء
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Correlation-driven screening of disorder is studied within the typical-medium dynamical mean-field theory (TMT-DMFT) of the Mott-Anderson transition. In the strongly correlated regime, the site energies epsilon_R^i characterizing the effective disorder potential are strongly renormalized due to the phenomenon of Kondo pinning. This effect produces very strong screening when the interaction U is stronger then disorder W, but applies only to a fraction of the sites in the opposite limit (U<W).



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